stroppy bird

Our 17 week old RIRs (and one black star) are still not totally identified as male or female. They've shown no signs of crowing and been fairly hen-like so far so we've assumed we can expect eggs sometime soon instead.

One of them has taken a real dislike to my husband though and started attacking him, pecking and twisting and really going for him whenever s/he sees him. I've been looking at them again this morning and two of them (including the feisty one) have slightly bigger combs than the other two and have one or two very long tail feathers where the other two have fairly stumpy tail feathers, so now I'm wondering if we have two roos and two pullets. I'll post some pics in the 'what breed or gender is this?' forum rather than clutter up here, but my behaviour question is what can we do to change this or do we just have an agressive bird? If it's a roo then we will likely get rid of it anyway but if it's a hen then we'd like to try and sort it out if that can be done. Any tips really appreciated